1,1-dialkyl naphthopyrans

ABSTRACT

Odoriferous agents in the form of certain novel 1,1-dialkyl naphthopyrans are disclosed. The 1,1-dialkyl naphthopyrans involved have the formula   WHEREIN R1 and R2 each represent a lower alkyl group having from 1 to 4 carbon atoms and the dotted lines indicate an optional double bond emanating from the carbon atom in the 4a position, and mixtures thereof. R1 and R2 preferably both represent methyl. Processes for the production of said 1,1,-dialkyl naphthopyrans are also disclosed.

United States Patent [191 Auger et al.

[ Aug. 26, 1975 1,1-DIALKYL NAPHTHOPYRANS [75] Inventors: Bernard Auger,Grasse; Pierre Resnelle, Le Cannet; Paul Jose Teisseire, Grasse, all ofFrance [73] Assignee: Societe Anonyme des Establissements Roure-BertrandFils & Justin Dupont, Paris, France [22] Filed: Feb. 2, 1973 [21] Appl.No.: 328,928

[30] Foreign Application Priority Data Feb. 16, 1972 France 725139 [52]US. Cl 260/345.2; 252/522 [51] Int. Cl C07d 311/02 [58] Field of Search260/3452 [56] References Cited UNITED STATES PATENTS 3,796,727 3/1974Deboer 260/3452 Primary Examiner.lohn M. Ford Attorney, Agent, orFirmWallenstein, Spangenberg,

Hattis & Strampel 5 7 ABSTRACT Odoriferous agents in the form of certainnovel 1,1- dialkyl naphthopyrans are disclosed. Thev l,l-dialkylnaphthopyrans involved have the formula wherein R and R each represent alower alkyl group having from 1 to 4 carbon atoms and the dotted linesindicate an optional double bond emanating from the carbon atom in the4a position, and mixtures thereof. R and R preferably both representmethyl.

Processes for the production of said 1,1,-dialkyl naphthopyrans are alsodisclosed.

14 Claims, No Drawings l. l DIALKYL NAPHTHOPYRANS DETAILED DESCRIPTIONOF THE INVENTION The present invention relates to naphthopyrans. aprocess for their preparation as well as to perfumes and odoriferousproducts containing said naphthopyrans.

According to the present invention there are provided naphthopyranshaving the general formula:

wherein R and R each represent a lower alkyl group having from I to 4carbon atoms and the dotted lines indicate an optional double bondemanating from the carbon atom in the 4a position. and mixtures thereof.

R and R" preferably both represent methyl.

The naphthopyrans according to the invention may be prepared bycondensing Z-hydroxyethyl-2-hydroxy decalin having the formula:

with a di-lower alkyl ketone having the formula:

lll

wherein R and R have the meanings given above, and then if desiredsubjecting the product to catalytic hydrogenation.

The ketone of formula III is preferably acetone. but other ketones suchas methylethyl ketone. methylisobutyl ketone, ethylisobutyl ketone,methyl-npropyl ketone or diethyl ketone may also be used.

The condensation is conveniently effected in a conventional manner usingan acid catalyst. Examples of suitable acid catalysts include sulphuricacid, perchloric acid, p-toluene-sulphonic acid and boron trifluorideetherate.

The condensation gives rise to a mixture of the isomers having thefollowing formulae:

1 2 H H R R IV v VIII

wherein R and R have the meanings given above.

Under the reaction conditions employed herein, the compounds having theformulae IV and VII are formed in the largest yields and the compoundshaving the formulae V and VIII only in a small proportion. Theindividual isomers of the mixture of isomers can be separated from eachother and isolated in pure form by conventional processes such as forexample by chromatography.

The starting material of formula II may conveniently be prepared byreducing a corresponding ester having the formula:

CHZCOOH x wherein R represents an alkyl group having from I to 6 carbonatoms. The reduction may conveniently be effected by conventionalmethods for example by treatment with sodium in a suitable solvent suchas anhydrous ethanol or with diisobutyl aluminium hydride.

The catalytic hydrogenation of the mixture of the iso-' mers IV to IX.toobtain the saturated compounds of formulae:

i R2 0 Y XI XII may be effected by conventional methods such as forexample using platinum or palladium on carbon or Raney nickel. as thecatalyst.

The starting material having the formula X may convenently be preparedby treating a mixture of cis and trans B-decalones with an a-halo esterhaving the formula: XCH- ,COOR wherein X represents a halogen atom.preferably bromine. and R represents an alkyl group having from 1 to 6carbon atoms, in the presence of zinc. The progress of the reaction canbe assisted by addition of a small quantity of activator for the zinc.Examples of suitable activators include iodine. mercuric chloride.mercuric bromide and copper. The group R is preferably methyl or ethyl.

The compounds of formula l have remarkable odours which are in generalreminiscent of the odour of ambergris. They are hence useful in thepreparation of odoriferous compositions. They may be used in thepreparation of perfumes as well as for perfuming commercial productssuch as toilet waters, cosmetics, soaps. washing liquids and otherproducts. The quantity in which the compounds according to the inventionmay be used varies widely, depending on the nature of the product andthe desired odour intensity. In the preparation of concentrates. thenaphthopyrans may for example conveniently be used in a proportion offrom 1 to 15% by weight. For the preparation of perfumes of the floraltype the compounds may be used in a proportion of 1 to by weight, andfor perfumes of the chypre" type in a proportion of from 5 to by weight.A proportion of from 5 to 10% by weight is also an appropriateproportion for the preparation of concentrates utilisable for perfumingsoaps. In certain applications concentrations of 1 to 5% by weight ofthe compounds of formula I, may be used.

The invention will now be illustrated with reference the followingExamples.

EXAMPLE 1 94 g of 2-hydroxyethyl-2-hydroxy-decalin are dissolved in 1500ml of acetone; 30 ml of concentrated sulphuric acid are added theretoand the solution is left for 7 hours at ambient temperature. Thesolution is then neutralised with 1000 ml of a 9% aqueous solution ofsodium bicarbonate, extracted with benzene and washed to neutralitythereby giving 70 g of crude product which are rectified. There are thusobtained 45 g of a mixture of decahydro-l,l-dimethyl-lH-naphtho-[2,3-c1pyrans and decahydro-l l -dimethyll H-naphtho-[1,2-c]pyranshaving the formulae IV to IX given above. This represents a yield ofabout 40%. The product has b.p. 8890C and 11,, 1.5110.

The starting material may be prepared as follows:

a. To 112 g of powdered electrolytic zinc which is covered by benzeneand to which has been added some crystals of mercuric chloride there isadded dropwise several ml of a solution composed of the followingmixture: 228 g of B-decalone, 228 g ofethyl bromoacetate and 450 ml ofanhydrous benzene. The mixture is then refluxed to initiate thereaction; once the reaction has started heating is stopped and the restof the solution is added so as to maintain reflux. After the addition iscompleted. refluxing is continued for a further 2 hours. After cooling,the mass is hydrolysed with 850 ml of a 10% aqueous solution ofsulphuric acid. The mass is then extracted with benzene, the benzenesolutions washed to neutrality. the benzene distilled and 330 g of crudeproduct are obtained which are rectified under 0.5 mm and which yield310 g of pure 2-carbethoxymethyl-2-hydroxy-decalin. Yield 86%, b.p.., 5l121l5C; n,,"" =1.4863.

b, 86.25 g of small pieces of sodium are added to 60 g of2-carbethoxy-methyl-2-hydroxy-decalin and 900 ml of anhydrous ethylalcohol. A vigorous reaction sets in which causes the reaction medium toreflux. Reflux is maintained for one hour. The mass is cooled. 1000 mlof water added. the alcohol distilled off and the residue is taken up ina little warm water. After cooling the mass is extracted three timeswith 250 m1 of diethyl ether. The ethereal solutions are washed toneutrality and distilled; there are thus obtained 40 g of crude productwhich are rectified under 0.5 mm. This rectification gives 22 g of2-hydroxyethyl-2 -hydroxy-decalin (b.p.., 138l40C), which represents aconversion of about 42%.

b A solution of 235 g of diisobutyl aluminium hydride in 300 ml ofanhydrous benzene is added dropwise to a mixture of 120 g of2-carbethoxymethyl-2- hydroxy-decalin and 120 m1 of anhydrous benzeneunder nitrogen. During the addition the temperature of the reaction massis held between 15 and C. This temperature is maintained for a further 2hours after the end of the addition. The mass is then cooled to 0C andhydrolysed with 1500 ml of a 10% aqueous solution of sulphuric acid. Thetemperature is allowed to return to ambient, the organic layer decantedand the mother liquor extracted twice with 250 m1 of benzene. Thebenzene extracts are then combined and washed to neutrality. Afterdistillation of the solvent on a water bath under reduced pressure thecrude product is rectified giving 72 g of2-hydroxy-ethyl-2-hydroxy-decalin (72% yield) having b.p. 147.

EXAMPLE 2 110 g of decahydrodimethylnaphthopyran prepared as describedin Example 1, is introduced into a 250 m1 autoclave followed by ml ofabsolute ethyl alcohol and 3.3 g of 5% palladium on carbon. Hydrogen isthen introduced under a pressure of kg/cm After 8 hours at 120C thehydrogenation is stopped. After cooling and filtration of the catalystthe alcohol is distilled off under reduced pressure and 100 g of crudeproduct are obtained which are rectified. There are thus obtained g ofaproduct (80% yield) having the following constants: b.p.., 96C; n,,""1.5010 and being a mixture of pcrhydro-l,1-dimethylnaphtho[ 2,3-c]-pyranand perhydro-l,1-dimethylnaphtho[ l .2-c]-pyran.

The use of the compounds of the present invention as odoriferous agentsis illustrated in the following Examples A to E.

Example A Concentrate for perfume -Continued -Continued 20 (.l laldehyde t l' i l. H1? in ethyl phtllalate 1U Patchouli oil 20 Rose ofMay absolute 2U (ivet absolute. in ethyl phthalate 8U Jasmin absolute 2UBenzoin resinoid 7t) Benzyl salieylate 4U Dioxa-2.7-cycloheptatleeanoneotl Dioxa-2.7-e \cloheptadeeanone. So"; in ethyl 5 5o Mixture ofphthalate perhydrol l -dimethyl-naphthol 2.3-e Ipyran and tit) \etiverylacetate perhydro-I .l-dil'l'lethyl-l'lapl'lthol 1.2-e lpyran lollMixture of the isomers ol'the aforesaid formulae l\' to loan IX HltltlExalnple E Perl'an'le (Foagere) Example B Concentrate tor perfume((hypre type) [(1 3o Petit min oi] Grass 3t) Linulol l0 Benzyl acetatel7() Bergamot Peel oil Extra Artemisia oil 280 Lemin Peel oil ExtraBergamot Zest Peel oil Extra 4() Sage Clary Grasse Lemon Peel oil Extra20 (ieranium Bourbon oil Linalol 2(1 (.12 aldehyde, 5% in ethylphthalate 5t) Lavender oil Laragne 50'; I5 40 Forest moss absolute l5Neroli oil It) Vetiver Bourbon oil 40 Ylang Ylang oil Nossi Be 100Hydroxyeitronellal 20 Rose of May absolute 40 st l dtl fl :o (.loaldehyde 1009; to); in ethyl phthalate 3 vt y .10 (.ll aldehyde loo /ll. low in ethyl phthalate 2U Dime-2.7-cyclohcntadccmwlw 5Uo-Amylcinl'lamicaldchyde 7U Lin lyl 2t) Coriander oil 20 I00 Mixture ofperhydro-l.l-dimethyl-naphthol Z 3-Ipyran 2 Galbanam oil andpcrhydro-l,l-din'lethyl-l'laphthol l.2-c lpyran. 5071 It) (ieraniuntBourbon oil in ethyl phthalatc 2U (ieraniol ltlUtl lUtlHydl'oxyeitrol'lnellal ltlt) Jasmin absolute It) Oak moss absolute 30Forest moss absolute 25 3t) Sandalwood oil East lndics 2U MethyliononeW6 ClfllmZ 1. Naphthopyrans of the formula 8 lsobutylqumolme lU Amyl tli'late 20 Benzyl salieylatc It) Sty rax oil 20 Vetiver oil Bourbon 2UCoumarin 3t) Dioxa-I.7-eye|oheptadeeanone. 50' in ethyl phthalate It)C416 aldehyde l()()'/r l(I"/1 in ethyl phthalate o0 Musk Ambrette 2UMusk ketone 70 Mixture of the isomers of the aforesaid formulae IV toExample C Toilet water I80 Bergamot Peel oil Eftra Z60 Lemon Peel oilExtra 20 Bornyl acetate 30 Scotch Pine oil 40 Linalol 2U GeraniumBourbon oil g wherein R and R each represent lower alkyl having 120Hydroxyeitronellal from 1 to 4 carbon atoms and the dotted lines indiy gcate an optional double bond emanating from the l 1 60 ia Carbon atom inthe 4a position. and mixtures 60 Sage Clary oil Grasse thereof. 20 Muskketone 4t) Mixture of the isomers of the aforesaid formulae IV toNlphthopyrans accordmg to clalm wherein R1 IX and R represent methyl. 3.A naphthopyran according to claim 1 in which said Example D P f (Chypm)naphthopyran ls 3,5,5a,6,7.8,9,9a, 10, lOa-decahydro-1,l-dimethyl-lH-naphtho[2,3-c]pyran of formula: 50 Benzyl acetate 5ULinalyl acetate I00 Lemon Peel oil Extra H 20 Coriander oil 5 Neroli oil50 Ylang Ylang oil extra 20 (.l l aldehyde. 10'? in ethyl phthalate IllC. 12 aldehyde. 5') in ethyl phthalate XIII 8U a-Hexyleinnamiealdehyde8U Jasmin absolute 3 50 Rose of May absolute 2U Citronellol CH 6UHydroxyeitronellal H 3 -10 Rose of the Orient oil l0 Styrallyl acetateCMWPhYHW-"I 4. A naphthopyran according to claim 1 in which said 30Forest moss absolute 15 -m naphthopyran ls3,4,5,5a,6,7,8,9,9a,l()-decahydro-l ,lyMethylionone dimethyll H-naphtho[2,3-c ]pyran of formula:

XIV

5. A naphthopyran according to claim 1 in which said naphthopyran is3,4,5a,6 7,8 9.9a, l (l. lUa-decahydrol,l-dimethyllH-naphtho[2,3-c]pyran of formula:

6. A naphthopyran according to claim 1 in which said naphthopyran isperhydrol l -dimethyl-naphtho[ 2.3- clpyran of formula: v,55/l() HEC CH7. A naphthopyran according to claim 1 in which said naphthopyran is3,5,6,6a,7 8,9. l O,l a, 1 Ob-decahydrol, l -dimethyll H-naphtho[ l 2-c]pyran of formula.

3 0 CH5 \I H i YVII 8. A naphthopyran according to claim 1 in which saidnaphthopyran is 3,4,5,6.6a,7,8,9.l() l()a-decahydrol, l -dimethyllH-naphthol l 2-c]pyran of formula:

XVIII 9. A naphthopyran according to claim 1 in which said naphthopyranis 3,4,6,6a,7,8 9 l 0,1011. lOh-decahydrol,l-dimethyl-l H-naphthol l2-c]pyran of formula:

10. A naphthopyran according to claim 1 in which said naphthopyran isperhydro-l,1-dimethylnaphtho[ l ,2-c]pyran of formula:

3 CH O 1 l. A process for the production of naphthopyrans of the formulawherein R and R each represent a lower alkyl group having from I to 4carbon atoms and the dotted lines indicate an optional double bondemanating from the carbon atom in the 4a position, and mixtures thereof,which comprises condensing 2- hydroxyethyl-Z-hydroxy-decalin having thefor mula H OH CH CH 0H II with a di-lower alkyl ketone having theformula:

0 ll R'-C--R- wherein R and R have the meanings given above.

12. A process according to claim 11, wherein R and R each represent amethyl group.

13. A process according to claim 11, wherein thecondensation is effectedin the presence of an acid catalyst.

14. A process according to claim 12, which comprises catalyticallyhydrogenating the product obtained by said process of claim 12.

1. NAPHTHOPYRANS OF THE FORMULA
 2. Naphthopyrans according to claim 1,wherein R1 and R2 represent methyl.
 3. A naphthopyran according to claim1 in which said naphthopyran is3,5,5a,6,7,8,9,9a,10,10a-decahydro-1,1-dimethyl-1H-naphtho(2,3-c)pyranof formula:
 4. A naphthopyran according to claim 1 in which saidnaphthopyran is3,4,5,5a,6,7,8,9,9a,10-decahydro-1,1-dimethyl-1H-naphtho(2,3-c)pyran offormula:
 5. A naphthopyran according to claim 1 in which saidnaphthopyran is3,4,5a,6,7,8,9,9a,10,10a-decahydro-1,1-dimethyl-1H-naphtho(2,3-c)pyranof formula:
 6. A naphthopyran according to claim 1 in which saidnaphthopyran is perhydro-1,1-dimethyl-naphtho(2,3-c)pyran of formula:v,55/10
 7. A naphthopyran according to claim 1 in which saidnaphthopyran is3,5,6,6a,7,8,9,10,10a,10b-decahydro-1,1-dimethyl-1H-naphtho(1,2-c)pyranof formula:
 8. A naphthopyran according to claim 1 in which saidnaphthopyran is3,4,5,6,6a,7,8,9,10,10a-decahydro-1,1-dimethyl-1H-naphtho(1,2-c)pyran offormula:
 9. A naphthopyran according to claim 1 in whicH saidnaphthopyran is3,4,6,6a,7,8,9,10,10a,10b-decahydro-1,1-dimethyl-1H-naphtho(1,2-c)pyranof formula:
 10. A naphthopyran according to claim 1 in which saidnaphthopyran is perhydro-1,1-dimethyl-naphtho(1,2-c)pyran of formula:11. A process for the production of naphthopyrans of the formula
 12. Aprocess according to claim 11, wherein R1 and R2 each represent a methylgroup.
 13. A process according to claim 11, wherein the condensation iseffected in the presence of an acid catalyst.
 14. A process according toclaim 12, which comprises catalytically hydrogenating the productobtained by said process of claim 12.